Periodic Table Study Guide

6th Grade ScienceMr Wegley

Borrowed from Mrs. Larosa

How to Draw Bohr Diagrams

Bohr Diagrams

1) Find your element on the periodic table.2) Determine the number of protons – it is

the same as the atomic number.3) This is how many protons you will draw

in the nucleus.

Bohr Diagrams

1) In the center of the paper draw that many protons.

+ +

++

++

+

Bohr Diagrams

1) Then find the number of neutrons by subtracting the number of protons from the atomic mass.

2) 12 – 6 = 63) Add that many

neutrons.

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++

++

N

N NN

N

N

N

Now for the

electronse-

Bohr Diagrams

• Find out which period (row) your element is in.

• Elements in the 1st period have one energy level.

• Elements in the 2nd period have two energy levels, and so on.

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Bohr Diagrams

Each level hold a different amount of electrons.1st holds 22nd holds 83rd holds 84th holds 185th holds 326th holds 327th holds 188th holds 8

Bohr Diagrams

1) Draw a nucleus with .2) Carbon is in the 2nd

period, so it has two energy levels, or shells.

3) Draw the shells around the nucleus.

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++

++

N

N NN

N

N

Bohr Diagrams

1) Add the electrons.2) Carbon has 6

electrons.3) The first shell can only

hold 2 electrons.

++

++

++

N

N NN

N

N

Bohr Diagrams

1) Since you have 2 electrons already drawn, you need to add 4 more.

2) These go in the 2nd shell.

3) Add one at a time -starting on the right side and going counter clock-wise.

++

++

++

N

N NN

N

N

Bohr Diagrams

1) Check your work.2) You should have 6 total

electrons for Carbon.3) Only two electrons can

fit in the 1st shell.4) The 2nd shell can hold up

to 8 electrons.5) The 3rd shell can hold 18,

but the elements in the first few periods only use 8 electrons.

++

++

++

N

N NN

N

N

Bohr Diagrams

Try the following elements on your own:

a) Hb) Hec) Od) Ale) Nef) K

Bohr Diagrams

Try the following elements on your own:

a) H – 1 electronb) Hec) Od) Ale) Nef) K

+

Bohr Diagrams

Try the following elements on your own:

a) Hb) He - 2 electronsc) Od) Ale) Nef) K

+

+N N

Bohr Diagrams

Try the following elements on your own:

a) Hb) Hec) O - 8 electronsd) Ale) Nef) K

OO

Bohr Diagrams

Try the following elements on your own:

a) Hb) Hec) O d) Al- 13 electronse) Nef) K

OO

Bohr Diagrams

Try the following elements on your own:

a) Hb) Hec) Od) Ale) Ne - 10 electronsf) K

NeNe

Bohr Diagrams

Try the following elements on your own:

a) Hb) Hec) Od) Ale) Nef) K - 19 electrons

KK

Bohr Diagrams

End of Study Guide.

You should know how to draw a Bohr Diagram for

the first 20 elements.